Hi, I am working on sound localization system. I want to find the co-ordinate of the sound source by least mean square method in MATLAB. I have the co-ordinates of the 4 microphones and the relative distance between mic 1 to the source to mic 2 to the source, i.e. the time delay*speed of sound. I even have the formulas but I have no clue on how to crack this: d12=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x2-xs)^2+(y2-ys)^2) d13=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x3-xs)^2+(y3-ys)^2) d14=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x4-xs)^2+(y4-ys)^2) d12, d13, d14 - relative distance bet the mic pairs 1,2 , 1,3 and 1,4 respectively. (x1,y1) - co-ordinates of mic 1 , (x2,y2) - co-ordinates of mic 2, (x3,y3) - co-ordinates of mic 3, (x4,y4) - co-ordinates of mic 4 Solving these simultaneously will give me (xs,ys) Any suggestions on how to do this.. ??

# LMS

Started by ●September 7, 2008

Reply by ●September 7, 20082008-09-07

On Sep 7, 4:38�am, "maz_p5" <maz...@hotmail.com> wrote:> Hi, > > I am working on sound localization system. I want to find the co-ordinate > of the sound source �by least mean square method in MATLAB. I have the > co-ordinates of the 4 microphones and the relative distance between mic 1 > to the source to mic 2 to the source, i.e. the time delay*speed of sound. > > I even have the formulas but I have no clue on how to crack this: > d12=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x2-xs)^2+(y2-ys)^2) > d13=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x3-xs)^2+(y3-ys)^2) > d14=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x4-xs)^2+(y4-ys)^2) > > d12, d13, d14 - relative distance bet the mic pairs 1,2 , 1,3 and 1,4 > respectively. (x1,y1) - co-ordinates of mic 1 , (x2,y2) - co-ordinates of > mic 2, (x3,y3) - co-ordinates of mic 3, (x4,y4) - co-ordinates of mic 4 > > Solving these simultaneously will give me (xs,ys) > > Any suggestions on how to do this.. ??Hire somebody who does have a clue how to crack it. Dirk

Reply by ●September 7, 20082008-09-07

maz_p5 wrote:> Hi, > > I am working on sound localization system. I want to find the co-ordinate > of the sound source by least mean square method in MATLAB. I have the > co-ordinates of the 4 microphones and the relative distance between mic 1 > to the source to mic 2 to the source, i.e. the time delay*speed of sound. > > I even have the formulas but I have no clue on how to crack this: > d12=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x2-xs)^2+(y2-ys)^2) > d13=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x3-xs)^2+(y3-ys)^2) > d14=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x4-xs)^2+(y4-ys)^2) > > d12, d13, d14 - relative distance bet the mic pairs 1,2 , 1,3 and 1,4 > respectively. (x1,y1) - co-ordinates of mic 1 , (x2,y2) - co-ordinates of > mic 2, (x3,y3) - co-ordinates of mic 3, (x4,y4) - co-ordinates of mic 4 > > Solving these simultaneously will give me (xs,ys) > > Any suggestions on how to do this.. ??Loads of papers on this. Do an IEEE Xplore search on acoustic source location. This is a non-linear problem but can be simplified in a number of ways. There are a good many methods.

Reply by ●September 7, 20082008-09-07

> > >maz_p5 wrote: > >> Hi, >> >> I am working on sound localization system. I want to find theco-ordinate>> of the sound source by least mean square method in MATLAB. I have the >> co-ordinates of the 4 microphones and the relative distance between mic1>> to the source to mic 2 to the source, i.e. the time delay*speed ofsound.>> >> I even have the formulas but I have no clue on how to crack this: >> d12=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x2-xs)^2+(y2-ys)^2) >> d13=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x3-xs)^2+(y3-ys)^2) >> d14=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x4-xs)^2+(y4-ys)^2) >> >> d12, d13, d14 - relative distance bet the mic pairs 1,2 , 1,3 and 1,4 >> respectively. (x1,y1) - co-ordinates of mic 1 , (x2,y2) - co-ordinatesof>> mic 2, (x3,y3) - co-ordinates of mic 3, (x4,y4) - co-ordinates of mic4>> >> Solving these simultaneously will give me (xs,ys) >> >> Any suggestions on how to do this.. ?? > >Loads of papers on this. Do an IEEE Xplore search on acoustic source >location. >This is a non-linear problem but can be simplified in a number of >ways. There are a good many methods. >Hi, I have done all my search and this is the equation what I have come up with; but how do i solve it in MATLAB. Any suggestions on it? Thank you.

Reply by ●September 7, 20082008-09-07

On Sep 7, 8:52�am, "maz_p5" <maz...@hotmail.com> wrote:> >maz_p5 wrote: > > >> Hi, > > >> I am working on sound localization system. I want to find the > co-ordinate > >> of the sound source �by least mean square method in MATLAB. I have the > >> co-ordinates of the 4 microphones and the relative distance between mic > 1 > >> to the source to mic 2 to the source, i.e. the time delay*speed of > sound. > > >> I even have the formulas but I have no clue on how to crack this: > >> d12=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x2-xs)^2+(y2-ys)^2) > >> d13=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x3-xs)^2+(y3-ys)^2) > >> d14=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x4-xs)^2+(y4-ys)^2) > > >> d12, d13, d14 - relative distance bet the mic pairs 1,2 , 1,3 and 1,4 > >> respectively. (x1,y1) - co-ordinates of mic 1 , (x2,y2) - co-ordinates > of > >> mic 2, (x3,y3) - co-ordinates of mic 3, (x4,y4) - co-ordinates of mic > 4 > > >> Solving these simultaneously will give me (xs,ys) > > >> Any suggestions on how to do this.. ?? > > >Loads of papers on this. Do an IEEE Xplore search on acoustic source > >location. > >This is a non-linear problem but can be simplified in a number of > >ways. There are a good many methods. > > Hi, > I have done all my search and this is the equation what I have come up > with; but how do i solve it in MATLAB. > Any suggestions on it? > > Thank you. �Look up "GPS equations," good books that describe how the GPS system works should have the solution. Julius

Reply by ●September 7, 20082008-09-07

On Sep 7, 6:52�pm, "maz_p5" <maz...@hotmail.com> wrote:> >maz_p5 wrote: > > >> Hi, > > >> I am working on sound localization system. I want to find the > co-ordinate > >> of the sound source �by least mean square method in MATLAB. I have the > >> co-ordinates of the 4 microphones and the relative distance between mic > 1 > >> to the source to mic 2 to the source, i.e. the time delay*speed of > sound. > > >> I even have the formulas but I have no clue on how to crack this: > >> d12=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x2-xs)^2+(y2-ys)^2) > >> d13=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x3-xs)^2+(y3-ys)^2) > >> d14=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x4-xs)^2+(y4-ys)^2) > > >> d12, d13, d14 - relative distance bet the mic pairs 1,2 , 1,3 and 1,4 > >> respectively. (x1,y1) - co-ordinates of mic 1 , (x2,y2) - co-ordinates > of > >> mic 2, (x3,y3) - co-ordinates of mic 3, (x4,y4) - co-ordinates of mic > 4 > > >> Solving these simultaneously will give me (xs,ys) > > >> Any suggestions on how to do this.. ?? >___________________________________________________________________> Hi, > I have done all my search and this is the equation what I have come up > with; but how do i solve it in MATLAB. > Any suggestions on it? > > Thank you. �______________________________________________________________________ I think this link should help......it's about solving simultaneous nonlinear equations, which is what I think you want to do.. http://www.mathworks.com/support/solutions/data/1-15NRJ.html?product=OP&solution=1-15NRJs

Reply by ●September 7, 20082008-09-07

On Sep 8, 7:36 am, Mandar Gokhale <stallo...@gmail.com> wrote:> On Sep 7, 6:52 pm, "maz_p5" <maz...@hotmail.com> wrote: > > > >maz_p5 wrote: > > > >> Hi, > > > >> I am working on sound localization system. I want to find the > > co-ordinate > > >> of the sound source by least mean square method in MATLAB. I have the > > >> co-ordinates of the 4 microphones and the relative distance between mic > > 1 > > >> to the source to mic 2 to the source, i.e. the time delay*speed of > > sound. > > > >> I even have the formulas but I have no clue on how to crack this: > > >> d12=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x2-xs)^2+(y2-ys)^2) > > >> d13=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x3-xs)^2+(y3-ys)^2) > > >> d14=sqrt((x1-xs)^2+(y1-ys)^2)-sqrt((x4-xs)^2+(y4-ys)^2) > > > >> d12, d13, d14 - relative distance bet the mic pairs 1,2 , 1,3 and 1,4 > > >> respectively. (x1,y1) - co-ordinates of mic 1 , (x2,y2) - co-ordinates > > of > > >> mic 2, (x3,y3) - co-ordinates of mic 3, (x4,y4) - co-ordinates of mic > > 4 > > > >> Solving these simultaneously will give me (xs,ys) > > > >> Any suggestions on how to do this.. ?? > > ___________________________________________________________________> Hi, > > I have done all my search and this is the equation what I have come up > > with; but how do i solve it in MATLAB. > > Any suggestions on it? > > > Thank you. > > ______________________________________________________________________ > > I think this link should help......it's about solving simultaneous > nonlinear equations, which is what I think you want to do.. > > http://www.mathworks.com/support/solutions/data/1-15NRJ.html?product=...Actually you obviously have not done a good enough search. the one thing you don't want to do is just go ahead and try and solve these equation as they stand. They need to be linearized first and there are numerous papers on this. For example Smith and Abel Closed-Form Least-Squares source location estimation from range difference measurements. IEEE Trans ASSP 35,12 Dec 1987. Loads more